Have you tried re-formatting the drive once it's fully recognised?
I can't claim to know this as an expert, but when you mention 'SAN' seems to indicate a proprietary filesystem that can be a bit rubbish.The reason I say this are that I own a Netgear SC101, a powered, network attached caddy that hold a pair of IDE drives. It has to format the drive sitself and uses this Z-SAN format and onboard software to work them. They're notoriously bad for not being found on the network or just crashing... I'm on the way to buying a new external USB drive to hold the remaining data on mine and getting it on ebay.